The invention relates to the field of elevator control, and in particular to the scheduling of elevators operating as a group in a building.
Group elevator scheduling has long been recognized as an important issue for transportation efficiency. The problem, however, is difficult because of hybrid system dynamics, combinatorial explosion of the state and decision spaces, time-varying and uncertain passenger demand, strict operational constraints, and realtime computational requirements for online scheduling.
Recently, elevator systems with destination entry have been introduced. In a destination entry system, passengers are asked to register their destination floors before they are serviced. More information is thus available for group elevator scheduling, since passenger destinations are now known when deciding on car assignments. Furthermore, with the progress in information technology, one promising direction is to use advance traffic information from various new sensor or demand estimation technologies to reduce uncertainties and significantly improve the performance. Near-optimal scheduling with advance traffic information will lead to better performance as compared to scheduling determined without the use of advance traffic information.